limepipes-plugin-api

LimePipes plugin API is a repository that contains the gRPC API definition for LimePipes plugins. These plugins are used to parse and/or export different file formats (Bagpipe Music Writer, MusicXML, ...). The underlying communication is done via Hashicorp's Go Plugin System.

Project Structure

This repository contains the API definition for LimePipes plugins and a music model that represents the parsed tunes from the supported file formats. The returned data structure from file parsing is called the music model which is a common representation of the parsed tunes. The music model structs contain struct tags to be exported to .yaml files.

Directory Structure

proto

Here are the protobuf files that define the gRPC API for LimePipes plugins and the music model.

musicmodel

The output directory for the generated code from the protobuf files for the music model. All files that do not end with .pb.go store utility methods for objects from the model. Many structs have a corresponding .yaml.go file which contains the MarshalYAML and UnmarshalYAML methods to serialize and deserialize them to and from YAML.

cmd

This directory contains some test and example code to implement a LimePipes plugin and the LimePipes plugin host.

plugin

The generated code from the protobuf files for the LimePipes plugin API. This code is used to implement the LimePipes plugins. It also contains the boilerplate code for go-plugin to create and use a plugin.

Build

buf generate builds all the generated code from the protobuf files.

Run

The limepipes application needs a configuration file called limepipes.env beside the executable or the environment variables from this file directly set to the environment of the application.

Develop

Prerequisites

In order to build the protobuf implementations, you need to have the buf tool installed and in your PATH.

Mocks are generated with [vektra/mockery](https://vektra.github.io/mockery/latest/installation) this also has to be in your PATH.

Build

The Makefile contains targets for many build and test tasks. The most important ones are:

• make build cleans all generated files and builds the protobuf code
• make format formats all protobuf files
• make test runs all tests on go files
• make check-coverage checks the test coverage of the go files

Quality assurance

The buf tool is used to lint and format the protobuf files. It is mandatory to have formatted and linted protobuf files in order to push changes to the repository. There is a GitHub action that checks the linting and formatting of the protobuf files. It also checks for breaking changes in the protobuf files so it should not be possible to introduce breaking changes without noticing.

Conventions

The API must utilize the return errors according to the gRPC status codes and the error codes defined in the grpc status codes page used by Google.

Used libraries and tools

• buf for protobuf handling
• Go Plugin System for plugin handling